xenapi: converting XenAPIVolumeTestCase to NoDB

* Uses NoDB base class for speedup
* Removes dead/unecessary code

Change-Id: I0aa8c0886801c2e0b331d0655170a48f37a874d5
compute tests: replace assertEquals with assertEqual

assertEquals will be deprecated in Python 3.

This is part of blueprint assertequal

Change-Id: Id639655621be04383fac986e8a0dc50a0951b64b
Always pass context to compute driver destroy()

The context arg was added to the compute driver's destroy() method in
commit 8c0673d3102478ef34ef1b11c1db156db4b68f62.  The context is used by
the libvirt driver when dealing with encrypted volumes.

Unfortunately, most of the places where this method is called in the
compute manager, the context wasn't being passed in.  This patch makes
the argument mandatory and updates all of the drivers to match.

Change-Id: Icea2a36c16869af43954065473ff4e4910f32b1e
nit: fix indentation

These lines (indented 3 spaces instead of 4) were making me twitch, so
fix it.

Change-Id: I7009214a44109b01a99531d7d84550eeafab6326
Imported Translations from Transifex

Change-Id: I70654c90973a2f89180694b1b4454d2f32d70f2d
Merge "nit: fix indentation"
Merge "Always pass context to compute driver destroy()"
Merge "xenapi: converting XenAPIVolumeTestCase to NoDB"
Merge "compute tests: replace assertEquals with assertEqual"